The present invention relates to methods and apparatuses for making a keyboard having a lighting system. The keyboard having the lighting system can be used in conjunction with a computer system.
A keyboard is commonly used in conjunction with a computer as an input device. Keyboards usually have a plurality of keycaps wherein alphanumeric symbols (or symbols in foreign languages) are printed on the keycaps to help users select the desired input to the computer. Under normal condition, such as under a brightly lit environment, the users typically have no difficulty using the keyboard since the symbols on the keycaps can be seen easily. However, in a dark environment or in a low ambient light condition, users are unable to see the symbols on the keycaps clearly or unable to see the symbols at all.
Various methods exist in the prior art for illuminating keyboards. For example, U.S. Pat. No. 6,179,432 by Zhang et al, contemplates a keyboard having an illumination panel inserted within the keyboard. The illumination panel in the keyboard in Zhang""s patent is placed between the keycaps and metal plate of the keyboard. Such an addition of the illumination panel requires reconfiguration of the keyboard. Further, integrating the illumination panel into the keyboard by placing the illumination panel between the keycaps and the metal plate of the keyboard decreases the key travel of the keyboard, which can be referred to as the downward travel distance for each key in the keyboard. In order to maintain the same key travel, the keyswitch mechanism in the key-board has to be re-designed and as such, will result in an increase in the overall thickness of the key-board. Reconfiguration of the keyboard thus imposes more unnecessary cost to the making of the keyboard. Also, illuminating the keyboards using such conventional methods requires extra power which is not desirable.
Exemplary embodiments of the present invention discloses an apparatus and a method of lighting a keyboard of a computer system that has a backlighting display system such as a notebook computer system.
In a conventional computer system with a backlighting display system, some light emitted from the light source is typically wasted as the light escapes at the end of a light guide panel. The present invention, in one embodiment, utilizes the unused light or the escaped light that is not used in illuminating the display assembly. Pluralities of light guide tubes are coupled to the light guide panel at the end portion where the light escapes. The light guide tubes capture the escaped or unused light that would escape at the end portion of the light guide panel. The light guide tubes redirect the captured light out of the display chassis. In one embodiment, the light guide tubes redirect the captured light so as to direct the light downward to illuminate the keyboard of the computer system.
In one exemplary embodiment, a light guide panel is disposed within a display assembly of a computer system. The light guide panel has a first end and a second end, wherein lights from a light source enter the light guide panel from the first end and exit through the second end. A light guide tube is coupled to the second end of the light guide panel. The light guide tube captures the lights that exit the second end and reflect the lights downward illuminating at least a portion of a keyboard of the computer system. The chassis that houses the display assembly includes a plurality of holes created along the top edge of the chassis wherein the lights captured and reflected by the light guide tube exit through the plurality of holes to illuminate at least a portion of the keyboard.
In another embodiment, an illumination system for a keyboard includes a light guide disposed within a display assembly of, for example, a laptop computer, and a reflector optically coupled to the light guide. The light guide may be the light guide that serves to spread light evenly across a display area of the display from a source of light such as a tubular light xe2x80x9cbulb.xe2x80x9d The reflector may be optically coupled to an end of the light guide to receive light from the light guide and to reflect the light out and onto the keyboard. The reflector may be a portion of the light guide itself positioned outside of the display area of the display area. The reflector may be positioned near an optically transparent, transmissive, or translucent aperture to allow light to be reflected out and onto the keyboard. The aperture need not be a hole but may be a transparent portion of a surface of a covering on the display assembly. The reflector is normally disposed outside of the display area (e.g., above the upper most portion of the viewable display area). The reflector reflects light outside of the display area and down onto the keyboard.